CHEMISTRY COMMUNITY

What is a salt bridge made up of and what is its purpose?

In a Galvanic cell, electrons flow form the anode to the cathode which results in solutions holding charges. The anode will become positive as it loses electrons, and the cathode solution will becomes more negative as it gains electrons. The salt bridge is put in place to neutralize the solutions. The negative ions from the salt (NO3-, if the salt is NaNO3 for example) will flow towards the anode to balance the positive charge forming, and the positive ion from the salt (Na+ for example) will flow towards the cathode to balance the negatively charged solution.

Salt bridge is usually made of inert anions and cations that balance out charge buildup.

The purpose of a salt bridge is to maintain charge balance because the electrons are moving from one half cell to the other. Without a salt bridge, the solution in the anode compartment would become positively charged and the solution in the cathode part would become negatively charged. This would create a charge imbalance that would cause the reaction to stop.

a porous disk can also be used for this purpose! that's just a membrane which balances charge

The salt bridge is essentially meant to neutralize solutions and balance the charges which occur due to the transfer of electrons in a redox reaction.

The purpose of the salt bridge is to prevent charge buildup; it is made up of a concentrated aqueous salt solution in an inverted, U shaped tube that allows the flow of ions that don't affect the cell reaction.

It just allows electrons to flow I think.

the salt bridge allows the flow of ions between the anode and cathode solutions.

I remember seeing somewhere that certain salts are not ideal for salt bridges... does anyone have an idea of what salts these include?

Salt bridges help with electron flow and neutralizing the solutions in a galvanic cell.

A sat bridge is usually comprised by a strong electrolyte which is further made up of ions. This salt bridge allows for the neutralization and flow of electrons between a cathode and anode solution. Without a proper salt bridge, the cathode solution will become negatively charged while the anode solution would become positively charged.